Winding for electrical machines



Dec. 6, 1932. G. ZIEGLER WINDING FOR ELECTRICAL MACHINES a sheets-sheetFiled Feb. 20, 1930 Dec. 6, 1932. G. ZIEGLER WINDING FOR ELECTRICALMACHINES s Sheets-Sheet 2 Filed Feb. 20, 1930 QM e W Dec. 6, 1932. G. ZIEGLER WINDING FOR ELECTRICAL MACHINES 3 Sheets-Sheet 5 Filed Feb. 20,1950 Patented Dec. 6, 1932 TES UNITED STA enone zrnenrre; or NUREMIBERG,GERMANY,

PAT-E NT oer-ice v ennmm Application filed February 90, I rsco, Serialno.

My invention relates to: electricrmachines and: more. particularly. to-a' winding for slotted? field-T magnets thereof.. The object-of myinventionis toprovide: a winding. simple to construct and. whiclr. is sodisposed! in the field magnet as toi'be easily removable for repairingin case of. defects arising in: one or several coils;v a

According to my'invention at least-themajority, if not all; of the coilsof the Wind'- ingwhich may be of the single or multilayer type-areassembled to form various groups of a particular type; Such-a complex ofcoils is called a coil: grate; The term grate, also used in the claims,:is chosen because the parallel sides of such a group'of coils-arealllocate'd: in one'layer'and resemble, as appears for: instance fromFig. 2', in their assemblv'the grate or a grate-sectibmoffa; furnace.Such a grate consists-of different coils displaced in relation-to oneanotherfboth coil sides being embedded in the slots'at the same depth:The coils oil a grate overlap one another; they do-not'.fhowever-,overlap the coils of the adjacent coi'l grates ofthe same layer.

The greatest advantages will he obtained if'i'n' all existingl'ayers'of' the winding, equal coil grates are formed'bf equal coilswith a slot pitch g; in such a manner that each coil grate is composedOffl/ coils and carried with its 21 coil sides in 22 successive slots.

The winding according to the invention may for instance-beadvantageously used for stators of" alternating current inductionmotors.

In. order that my invention mayheclearly understood reference will hemade to-the accompanying drawings {in whichare shown two examplesoftwo-layer windings embodyi'ng my invention and in which Fig-1 is adeveloped front view of one half of the stator circumference providedwith twelve slots, of a four pole three-phase induction motor' with twoslots for each pole and phase and having a coil grate at the bottomlayer', the coils of which. aredimensioned withv aslot pitch y=6-, i.e-.. equal to the numberof slots for each: pole, avso-called wmnmeronEEECTR'ICAL MACHINES 431 034; and in Germany February 16,1929.

p windins bing in thiscase. in-

vol-ved;. q I .1 Fig. 2 isz-the'plan -of the stator;-portion shown inFig. 1 in the axial direction;

--Fig.-.3 is aidiagram ofthe complete winding show-n1 partly in Figs 1and 2. It is-a developed front view of the'entire stator circumferencewith theuends of the: coilsides represented by circles and with the coilends turned downin the plan of the drawings.

Fig.4 is a front view of the stator with the winding-designed accordingtoF-igsi 1-3. Fig. 5is the.- diagram shown in a manner correspondingtothat of. Fig. 3 of a six-pole winding with six slots for-each-polewhich according to; the invention is constructed. of equals coils with;aipitch y 5 with six coil grates, whereby filling coils and'nising coilsare utilized.

Fig.6; is shown a complete developed circumferentiall view-of thediagram of the Winding. according to Fig. '3, and in' Fig; 7 a similardiagram of the winding according to Fig.5. v i The coils placed in thebottom layer-are in dicatedbyheavy Linea-those placed in the top layerby light Lines; furthermore the coilsin Fig. 7 which belong to variousphases are represented. by dash lines and dot-anddash lines. ReferringtoFigs. land 2 of the drawings the illustrated circumferential half ofthe slotted stator magnet has twelve slots indicated by' the referencenumerals l to 12. At the bottom of these slots commencing with slot 1are located the six equal coils a, b, a, (Z, 6, f in-such a-manner thatas shown in Fig. 2, they overlap one another and, as illustrated in Fig.1',.lie at the bottom of the slots each with both sides. The coils aredesigned with the pitch 6. The six coils together form a coil grating Rwhich with its twelve coil-sides is imbedded' in the twelve consecutiveslots.

When this coil grating of the bottom-slot layer has been placed inposition a similar coil grating R Fig. 2, is inserted into the remainingtwelve slots-as part of the slot bottom layer, proceeding along thecircumference in the same direction. The bottom halves of all the slotsare now occupied- In the slot top layer the coil grating R and R are nowformed from coils arranged similar to the gratings R and R \Vhen formingthe grating R the first coilside is placed into the slot 7. The gratingR thus occupies the top layer of slots 7 to 18 and the adjoining gratingR; the top layer of slots 19 to 2 1 and l to 6, as shown in Fig. 3 ofthe drawings.

By displacing the coil gratings of the slot top layer in relation to thecoil gratings of the slot bottom layer, the result is attained that thethickened outside ends of gratings of each layer produced by the outsideoverlapping of the coils are locatedinthe spaces between the thickenedgrating ends of the other layers. This is particularly clearlyillustrated in Fig. 4, and also in Figs. 1 and 2, where the outlines ofthe coil gratings R and R of the top layer are indicated in dottedlines. This arrangement has the advantage that the space is reducedwhich the parts'of the winding structure located outside the magnetstructure require in-the radial direction.

In Figs. 3 and 6 are also shown the external connections of the coils bywhich the winding structure is electrically subdivided into three equalstar-connected phases and displaced in relation to one another by 120electrical degrees.

As will be seen from the figures the windings of the several layers areinterlinked with one another only by the external connections.

The coil pitch y may ina known manner also be made smaller than thenumber n of slots per pole and phase with aview. to saving copper forthe end connectors. The socalled corded winding is then obtained. It mayhappen, that after the insertion of the largest possible number of coilgrates, some slots remain empty, which are designated here as residualslots. In this case the winding is made of two layers and at least aportion of the residual slots is occupied by the rising coils, which arepreferably designed with the same pitch 3 as the coils of the grates,and which are placed in the known manner each with one side in thebottomlayer and with the other side in the top layer of the winding.When using such rising coils which may be grouped together or bedistributed over the circumference of the winding, the two layers ceasebeing independent since they are not only electrically interlinked withone another by the external connections but are also interleaved withone another by reason of the rising coils.

If it should happen when carrying out the two-layer winding that afterinserting the closely disposed coil grates of the bottom layer, a numberof residual slots remain empty, the number of which is greater than thecoil pitch 3 and that only coils with the same pitch should be used forthe entire winding,

the residual slots will be overlaid in another way.

Such a winding is schematically shown in Figs. 5 and 7. The two-layerwinding is substantially composed of the coil grates R R R in the bottomlayer and of the coil grates R R and B in the top layer. The grates areequal, each consisting of five equal coils with the pitch 5 so that eachofthe grates has its. coil sides disposed in success'ive slots. Afterthus placing the three closely adjacent coil grates R R and R of thebottom layer, six residual slots 31-36 remain empty. .;=;The fillingcoil 9, which is also designed with the pitch 5, is at first embeddedin:the-bottom'of two of these residual slots, the total number of whichslots. is by ..-l greater thanthecoil pitch. In. the bottom of theremaining four residual slotsw32-35 is embedded one side'each of thefour rising coils h i, 70,- Z. The other side of these rising coils isused as the top'layer for one-of each of the coil sides of the coilgrate. R i.- e. the right hand side of coil his carried'as thetop layerin slot 1, the coil i'as top layer in slot 2, the coil is in the slot'3,and the coil Z in the @A filling coil m is then placedin the top layerof'slots 36 and 5, said ooil'bei'ng located-in the same way in relationto the rising-coils as 'the filling coil" g; in the bottom layer.By.reasonof the presence in .the upper layer of bothsides of the:filling coil m and of he four upper sides of the rising coils, six oithe" thirty-six slot spaces ofrthe top layer are filled, so that exactlythirty ,upper slotspaces remain .free for the=three coil grates-of thetop layer each"with tencoil sides disposed exclusivelyin the top layer.

- The connections bymeansi'of which this winding structure can beelectricallysubdivided into'three phases are not shown in Figs. 5 and?.of the drawings. The three phases are not accurately equal. The windingon being excited by a. revolving pole wheel with six poles wouldthussupply voltages difiering slightly .from. one another in value and notdisplaced from one another in phase by accurately120 degrees. v

In this winding structure also the thickened coil ends of the gratingsof each layer lie in the spaces between the coil ends of the gratings ofthe other layer as shown in Fig. 5.

The modeof filling up the residual slots illustrated in Fig. 5 is by nomeans the only possible one. The coil gratings R R R of the bottom-slotlayer might, for. instance, also be so inserted that between any two ofthem there remain two residual slots and these six residual slots mightbe occupied with three times two rising coils.

' The advantage of the method is that repairs of the winding are greatlyfacilitated. For instance if a coil of a single-layer winding structureshould become defective, it

would in the most unfavorable case only be necessary to remove a wholecoil grating in order to renew the defective coil. In the most favorablecase, viz. if the defective coil is the last placed coil of a grating,only this coil need be removed.

In the case of a two-layer winding the above holds good for the toplayer of the slots. If a coil of the bottom layer is damaged it is onlynecessary to remove two coil gratings of the top layer, in order torender accessible the grating of the bottom layer which contains thedefective coil.

To emphasize this advantage more fully it may be pointed out that incase of adefect in a coil of a double-layer winding structureconstructed, in the usual manner, of equal coils located with one sidein the slot top layer and with the other side in the slot bottom layer,it is not possible to remove one or more coils completely, i. e. withboth sides, from the iron body and to replace it by a new one, withoutlifting the sides of all coils, located between the sides of thedefective coil. The distortion or warping of the coils caused therebyhas frequently led to injuries also of these coils, which in extremecases may have the result that on account of originally only one or twodefective coils it is necessary to replace the entire winding.

The advantage mentioned is greatest if the multi-layer winding structureis carried out without braiding by rising coils.

I claim as my invention:

1. In electric machines or the like, an armature member having slotsdistributed over its face, a multi-layer winding composed of a pluralityof coils of suitable pitch carried in said slots, the said coils beingdivided into groups, each group forming a grate, said grates beingdisposed closely adjacent to one another, the several coils of eachgrate being displaced in relation to one another along the armature faceand overlapping one another and having both sides located at the samedepth in their respective slots.

2. In electric machines or the like, an armature member having slotsdistributed over its face, a i'nulti-layer winding composed of aplurality of coils in each layer carried in said slots, the coils ineach layer being divided into equal groups and having the slot pitcheach group forming a grate and consisting of 1 coils whose sides aredisposed in 2y sue-- cessive slots, the grates being closely adjacent toone another along the armature face, the several coils of each gratebeing displaced in relation to one another along the armature face andoverlapping one another and having both sides located at the same depthin their respective slots.

3. In electric machines or the like, an arr mature member having slotsdistributed over its face, a two-layer winding composed of a "pluralityof ooils' carried in said slots, the top 'aind --'bottom' layer ofsaidwinding each beiing divided into several groups of coils, of "the slotpitch y, each group forming a' grate -eonsisting of y o'oils whosegsides are'disposed in 23 successive slots, the gratesin'both layers;beiug'fd isposed closelyadjacent to one another a'ldn g the armatureface, the grates of the top layer beginning at a point coinciding atleast approximately with the centre of a coil grate of the bottom layer,the several coils of each grate being displaced in relation to oneanother along the armature face and overlapping one another and havingboth sides located at the same depth in their respective slots.

4. In electric machines or the like, an armature member having slotsdistributed along its face, a multi-layer winding composed of aplurality of coils in each layer, carried in.; said slots, the coils ineach layer being divided into groups of coils of the slot pitch eachgroup forming a grate and consisting of y coils, whose sides aredisposed in 21 successive slots, the grates being disposed closely 9adjacent to one another along the armature face, the several coils ofeach grate being displaced'in relation to one another along the armatureface and overlapping one another and having both sides located at thesame depth in their respective slots, the total number of the slots,being greater than the total number of coil sides of all grates capableof 'being embedded in one layer, and rising coils disposed in at least aportion of the slot spaces not taken up by grate coil sides, the sidesof said rising coils being disposed in the several layers of thewinding.

5. In electric machines or the like, an armature member having slotsdistributed along its face, a two-layer winding composed of a pluralityof coils, carried in said slots, the coils in each layer being dividedinto several groups of coils of the slot pitch 3 each group forming agrate and consisting of 3/ coils whose sides are disposed in 2ysuccessive slots, the grates in both layers being disposed closelyadjacent to one another along the armature face, the several coils ofeach grate being displaced in relation to one another and overlappingone another and having both sides located at the same depth in theirrespective slot-s, the total number of slots being greater than thetotal number of coil sides of all grates, capable of being embedded in alayer, and a plurality of interlinking residual coils of the slot pitchg for the residual slots, the number of said residual coils beinggreater than 3/, the highest possible number of the residual coils beingdisposed with both sides in the bottom spaces of said residual slots, anumber of said residual coils being rising coils disposed in the stillremaining residual slots and lying with one side in the bottom layer andwith he other side in the top layer 01:, the winding, and anothernumber'of-re- 1 i sidu'al coilsf corre'sponding-in number to the number ofresidual coils embedded in the r bottpm spaces 0f "said residual slots,and of f of; said rising coils.

Intest' we I d risingi coils-being wrapped around the sides ny whereof Ieifix mysignatuie. GEORGZIEGLER.

